March 20, 2024 — Ectrims Insights
Migraine is generally considered a common condition in people living with multiple sclerosis (MS) [1]. Back in 1952, D. McAlpine and N. Compston intended to describe “some aspects of the natural history of disseminated sclerosis” [2, p. 135]. They investigated a group of 250 individuals with MS and reported that five of them had experienced migraine in the three months before the onset of the disease. All five patients had a previous history of migraine [2, 3]. More recently, F.L.A. Yusuf and co-authors reviewed 29 studies and found that people with MS commonly experience migraine before the onset of the disease [4]. The prevalence of migraine in patients with MS varies across different countries – higher in American and African countries (43%), lower in European and Asian countries (25% and 24%, respectively) [5]. Researchers are investigating why migraine and MS can occur together.
What is the relationship between migraine and MS?
Ruth Ann Marrie, the Past Chair of the Medical Advisory Committee for the MS Society in Canada and a professor at the University of Manitoba, says, “Migraine is what we call episodic headache. Typically, people with migraine experience periods of throbbing headache, which can concern one half of the head or the entire head. In these periods, people can be sensitive to bright lights, sounds or strong smells. Therefore, people with migraine prefer to quietly lie down in the dark. The headache, which is sometimes accompanied by nausea or vomiting, can last on average a couple of hours or shorter if one takes medications. However, for some people, headaches can be longer lasting.” The episodes of headache are interspersed with periods of complete freedom from symptoms [6].
Disentangling the nature of the possible co-occurrence of migraine and MS poses a significant challenge. Recently, M.K. Horton and co-authors found no evidence indicating that migraine is a causal risk factor for MS. However, they identified several genetic variants shared between MS and migraine. This can partially explain the overlap between the two conditions [7]. Moreover, among the Northern California MS cohort, people with MS who experienced migraine – 38.9% – were more likely to be female, have ever smoked, and have a history of depression compared to people with MS who did not have migraine [7].
The timing of the diagnosis of migraine in people with MS can also vary. Professor Marrie added, “Some people can have migraine long before any symptom of MS, whereas others may develop or be diagnosed with migraine after the diagnosis of MS. One aspect to consider is that people with MS see neurologists more often, compared to the general population. Therefore, there is a possibility that some of the differences that we see in the timing of labelling of migraine in people with MS is related to the fact that most of them regularly see a neurologist. I saw many people who clearly had a history of migraine, but only got a label during neurological visits for MS. This is one factor that can influence the timing of when these diagnoses appear.”
Migraine and MS in clinical trials and healthcare
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